The present invention relates to a laminating machine particularly for through-sawing slabs made of granite and the like.
In the working method of slabs made of granite or of mining materials which have a hardness equal or very close to that of granite, a method for the production of either polished plates or of tiles obtained from slabs is performed which entails the polishing of both faces of the slab being processed and the subsequent through-sawing of the slab to obtain plates which are thinner than polished slab obtained without lamination.
The actual technical problem is related to the through-sawing of the slab into thinner plates. Splitting machines which have various solutions to the technical problem have in fact been used so far, but said machines can be traced back to two slabs working methods: horizontal working and vertical working.
In horizontal working, the plate is carried by a conveyor belt on a table, and through-sawing of the slab is performed by at least one train of diamond disks with progressively increasing diameters which are arranged parallel to the table. However, this method has numerous disadvantages. The most severe one is related to the cooling of the diamond disk during cutting, which is severely hindered by the horizontal position of the slab and of the disk, therefore entailing a very rapid wear of the diamond-bearing portion of the disk. Another disadvantage is constituted by the need to move the diamond disk so as to keep the cutting depth constant as a function of the wear of said disk. The above described problems cause this method to be used in practice only for relatively less hard materials, such as for example marble.
Vertical working entails the guiding of plates below a train of diamond disks with progressively increasing diameters so as to saw through the thickness of the slab. The problem is related to the guiding, which can cause the slab to oscillate so as to increase the wear of the diamond-bearing portion of the disk, furthermore causing an asymmetrical splitting of the slab, i.e. the lack of equal thickness in the two resulting plates.